PROBLEM: Approximately 1 Million dental implants are placed worldwide each year and this number is expected to increase at a rate of 10% per year. Current studies suggest that only 9.8% of implants are optimally placed and that deviation from planned, optimal sites can be as much as 3.5 mm. Optimal placement is necessary to improve implant success and reduce complications. This must be accomplished while reducing radiation exposure to the patient. METHODS: This in-vitro study will: 1) test the accuracy of computer guided dental implant placement, 2) evaluate the effect of the reduction of radiation exposure on the accuracy of computer guidance and 3) compare the actual and planned location of implants placed with Computed Axial Tomography (CT) computer guidance to the actual location of the implants placed with Cone Beam Computed Tomography (CBCT). Comparison of computer modeling done with (CT) and (CBCT) will be made. Standard clinical protocol will be used to place implants in plastic models simulating human mandibles and in actual human skulls. CT and CBCT systems will be used and the variables (planned location vs. actual location; planned vs. actual angulation) will be compared and statistically analyzed in three dimensions. RELEVANCE: A 3.5 mm variation in implant placement is considered clinically significant and can lead to complications. Methods to reduce/eliminate this variation will be addressed during this study. A new technology, the CBCT scanner involves 65% less radiation exposure and is considerably less expensive than the CT scanner, however some anatomic structures may not be as readily visible. Over [600] CBCT scanners are in use worldwide. It is important that the accuracy of these and future systems be tested in facilitating highly accurate implant placement while reducing radiation exposure. The results of this study will lay the foundation for future in vitro testing of the accuracy of simulated implant placement systems. is uploaded in the PHS 398 Research Plan Section. [unreadable] [unreadable] [unreadable]